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Phantom30

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About Phantom30

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  1. They are nice. I have one just like that only the FP bolt hole has been jetted out some. These things are caliber dependent like all other non-standard designs in this class AR frame. so look at the end of the Prime Punch thread if you are building a 6.5CM. If not then enjoy, it looks and really is nice.
  2. Davidson Defense bolt is working fine in the 24" rifle. Although I don't know if it would punch primers as the Toolcraft NiB 308W BCG did in the 22" rifle with the same hotter ammo lot. The 24" rifle now has the benefit of the nice Toolcraft NiB carrier from the damaged BCG instead of the old KAK carrier. Eventually the 24" Toolcraft carrier with Davidson Defense bolt BCG will be replaced by another Toolcraft 6.5 CM specific dual ejector BCG when the funds are available. This exercise has highlighted the fact that 6.5CM has caliber unique issues and has the potential for problems when using a standard AR-10 308W BCG. Therefore, it is obvious that if a company like Toolcraft has developed, produced and distributed a 6.5CM specific BCG then any 6.5CM AR builder should consider that fact and go with the BCG designed specifically for that caliber rifle. Both single and dual ejector models are available but since the caliber is reported to have potential ejection issues, then way not just go with the dual ejector and be done with it. The Toolcraft dual ejector design is different then other dual ejectors and I would suspect, if you may, that they did it right.
  3. don't know much about a 260 Rem other that the public SAAMI
  4. above "cold" should be "could" and "spherically" should be "specifically", too slow on edit again
  5. The one time test and data was sent to Hornady in July 2018. Never said break. The dents would probably have a minor effect on ballistics since the spin rate is so high and the mass of the plastic low. On the other hand where the tips were lead the deformation effected the mass distribution and dramatically demonstrated the effect. Granted those tips should not be used in an AR format but the effect changed concentricity and opened up accuracy. The point of the Lead tip test is to demonstrate that the forces encountered during chambering where significant. Copper OTM or HP although a much harder material still cold produce a flyer on occasion. Your vast experience with 260 Remington is not the same as the chambering issues with a Creedmoor. Recommending a Toolcraft BCG is a good thing but for a Creedmoor since it has been reported to have ejection and primer punch issues, the recommendation should include the high pressure 6.5 CM specific versions, single or dual ejector. In the velocity measurement chart it was noted that the post burn thru shot primers were all burred, on either brand of ammo used. This would indicate that the burn thru jetted the FP hole in the bolt face making it unsafe. The image of the primers fired using the new bolt installation shows a nice small strike pockets. Both ammo lots were tested with the new BCG, one fired hot lot ammo primer did show a slight ridge. No chronograph was allowed during this verification exercise so you couldn't attribute a velocity to that casing. Lessons learned here is that vendors advertise their BCGs will work in Creedmoor ARs, I am sure that's true but to be fully truthful the BCG should be the type spherically designed for the Creedmoor AR.
  6. Barrel parts is White Oak Armament (WOA) can't believe this thread has gone on this long with out somebody say you need to get your gas tubes there plus blocks etc. https://www.whiteoakarmament.com/shop/upper-parts-248/barrel-group.html I have found the in a 6.5CM you might consider the Toolcraft dual ejector 6.5CM specific BCG, it has the smaller FP diameter The ACC break is good have one on my 300WM and the interface to less noise works well.
  7. Thanks SS the bolt change recommendation solved the problems. Switched from the 308W Toolcraft single ejector NIB BCG to the Toolcraft 6.5CM small tip FP 0.065" instead of 0.077" plus dual ejector. Plus thoroughly clean chamber more often with 308W AR brushes and mop. All is now well, shooting sub-MOA with my cheapest parts I can find DIY built rifle.
  8. GR "That's a singular issue, with a singular user here, and singular use of the cheapest parts he can find to build a gun. That's all that is... " Interesting assessment thanks for the help. You really are near a desert border
  9. That rifle fired some of the round count in previous lots in the total S&B count. Not involved in the lot 16/78 count under consideration. The BCG in this rifle is a Toolcraft NiB, with standard 0.077" FP tip, single ejector. Barrel is a 22" bear creek Arsenal (BCA) SS straight fluted 1:8 twist, 6 grove 6.5 Creedmoor chamber with their standard barrel extension. The receivers are AP, gas system is WOA standard rifle length AR-10 gas tube with large match block. JP recoil eliminator break. Recoil system AP. The SAAMI standard nominal velocity for 140gr 6.5 CM is 2690 + 90 FPS, even the so called hot box was well within the manufactures standard. The COAL on the Defender rounds was 2.805, Hornady ELD 2.805, S&B FMJ was 2.740, SAAMI Mean average pressure limit is 62kpsi. The standards do not discriminate between bolt guns and gas guns so they should be equally capable of firing factory ammunition.
  10. The Davidson Defense bolt is in a KAK carrier in the 24" gas gun not involved here. Any switch in BCG's would have happened prior to the purchase of the 16/78 lot in question, so the round count stands.
  11. No the head spacing has not been verified or compared Yes probably next step now, is to get the tool craft Creedmoor bolt, as shooterrex and survival shop have recommended
  12. 392heminut The last three of my posts go together, the muzzle velocities are choreographed and the casings have a direct one to one correlation. willbird This thread is not about caliber to caliber performance but about the specific function of my 22" Creedmoor AR and the effects of ammunition. chambering and the BCG It has been purported that the culprit is the factory ammunition lot being more energetic than normal lots. In this case that has been shown to be relevant, but it still doesn't answer why this rifle has started to eat primers verses the bolt gun firing the same ammunition. Why does the bolt gun primers remain normal and the AR is leaving the primes raised and burred using multiple brands of ammo boxes shared between the two types of rifles. Why has this BCG started to fail to eject the last round in a stack? Has the primer burn thru effected the ejector, which by the way does appear scorched on the outer side.
  13. The evidence from the small samples above does show an increase in muzzle velocity between lots 11/10 and 16/78. However, the difference didn't cause punched primers in the bolt gun. All of the bolt gun primers felt smooth. The near same velocities in the AR all caused flowing primer strikes on two different brands of rounds and all post strike primers felt burred to the touch. Something other than ammunition lot muzzles velocities is happening here, which is the point in the origin of this thread.
  14. The primers for the above test shots
  15. Bolt gun, AR and ammo comparisons
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